JP2633958B2 - Discharge paper stacking device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a discharge paper stacking device provided in, for example, a copying machine for stacking sheets on which images output from the copying machine have been copied. .

[Conventional technology]

This type of conventional paper output stacking device has a paper output tray for receiving paper discharged from a paper output unit. The distance between the paper output unit and the top sheet stacked on the paper output tray, that is, the head, is properly adjusted to ensure that the paper discharged from the paper output unit is stacked on the paper output tray. Need to be managed. For this reason, the discharge tray is moved up and down by a tray elevating motor in accordance with the amount of sheets stacked on the discharge tray.

Conventionally, as a configuration for managing the head, the discharge state of the paper from the paper discharge unit is constantly detected by a sensor, and the paper discharge tray is gradually lowered according to an increase in the amount of paper on the paper discharge tray. There is something to make it happen. An upper limit sensor and a lower limit level sensor for setting an upper limit and a lower limit of an allowable range of a head are provided. First, when sheets are not stacked on the sheet discharge tray, the sheet discharge tray is set to the lower limit position. When the upper limit level sensor is turned on by the uppermost sheet and the lowermost level sensor is turned on by the uppermost sheet, the sheet discharge tray may be lowered to a position where the lower limit level sensor is turned on.

[Problems to be solved by the invention]

However, in the former configuration, since the discharge state of the paper from the paper discharge unit is always detected, a heavy load is imposed on the load of the tray elevating motor and the like, and the life of these loads is shortened. Further, there is a problem that the load on the control circuit of the tray elevating motor increases. On the other hand, the latter configuration requires two sensors, an upper limit level sensor and a lower limit level sensor, in order to set the range of the head, resulting in a problem that the number of parts increases and the cost increases. doing.

[Means for solving the problem]

In order to solve the above-mentioned problems, the paper output stacking device of the present invention is provided with a paper output tray below the paper output unit for receiving and stacking the paper discharged from the paper output unit. In a discharge paper stacking device that is moved up and down by a tray lifting motor, the uppermost sheet stacked on the sheet discharge tray or the upper surface of the sheet discharge tray in a state where sheets are not stacked is a drop between these and the above-described sheet discharge section. A drop sensor for detecting the lower limit position of the discharge tray, a tray lower limit switch for detecting the lower limit position of the discharge tray, a timer for measuring a predetermined time, and a top sensor on the discharge tray by the drop sensor. When it is detected that the paper or the upper surface of the paper discharge tray in which the paper is not stacked is at the lower limit position in the allowable range of the head and the above paper discharge unit, the paper on the paper discharge tray is detected. of In response to the output operation, the timer starts counting the time, and when the timer counts down, the tray elevating motor is operated to lower the sheet discharge tray. And control means for stopping the tray elevating motor and clearing the timer when it is detected that the lower limit position in the allowable range of the head with respect to the paper discharge unit has been reached. The discharge tray is gradually lowered until the tray lower limit switch detects that the discharge tray has reached the lower limit position.

(Operation)

According to the above configuration, the control means uses the head sensor to move the top of the uppermost sheet stacked on the sheet discharge tray or the upper surface of the sheet discharge tray in a state where the sheets are not stacked, to the head between the sheet and the sheet discharge portion. When it is detected that the sheet is at the lower limit position in the allowable range, the timer starts counting the time in accordance with the sheet discharging operation on the sheet discharging tray. During the time counting operation by the timer, the paper is discharged from the paper discharge unit, and the paper is accumulated on the paper discharge tray. Therefore, the time measured by the timer does not exceed the upper limit of the allowable range of the drop at the time of the end of the time, in consideration of the amount of paper discharged from the paper discharge unit per unit time. It is set to such time.

Next, when the time measurement by the timer is completed, the control means operates the tray elevating motor to lower the discharge tray. Then, when the drop sensor detects that the uppermost sheet on the sheet discharge tray has reached the lower limit position, the tray lifting motor is stopped and the timer is cleared.

By repeating such control, the drop between the sheet discharge unit and the topmost sheet on the sheet discharge tray is set within the allowable range where the sheets discharged from the sheet discharge unit are accurately accumulated on the sheet discharge tray. Can be held. In addition, when the paper is smoothly discharged from the paper discharge unit, the paper discharge tray does not move up and down, but only performs an operation of gradually descending as time passes when the paper is discharged. , Ie, continuous discharge of paper from, for example, a paper discharge unit of a copying machine.

〔Example〕

One embodiment of the present invention will be described below with reference to FIGS.

As shown in FIG. 2, the discharged paper stacking device 1 is provided on the paper output side of the copying machine 2. The copying machine 2 is provided with a pair of paper discharge rollers 3 near the paper output side surface, and the paper onto which the image is transferred is output from the paper output unit 4 by the paper discharge rollers 3.3. ing.

The paper output stacking device 1 has a paper output unit 5 that communicates with the paper output unit 4 of the copying machine 2. The paper output path 5 is connected to a pair of paper output rollers 7 Has reached. Paper discharge roller 7
Below the paper discharge tray 7, there is provided a paper discharge tray 8 for receiving and stacking the paper discharged from the paper discharge unit 6 by the paper discharge rollers 7. The paper discharge tray 8 protrudes in the paper discharge direction. Two guide rollers 9.9 are provided at the upper and lower ends of the discharge tray 8 on the copying machine 2 side. These guide rollers 9.9 are tray guides 10 extending vertically.
The discharge tray 8 can be moved up and down by such a structure. The end of the paper discharge tray 8 is a belt.
The belt 11 is connected to pulleys
It is hung on December 13. In the vicinity of the lower pulley 13, a tray elevating motor 14 is provided.
The rotation shaft 14 and the pulley 13 are connected by a belt 15. Therefore, the discharge tray 8 is moved up and down by the forward and reverse rotation of the tray elevating motor 14.

Further, a head sensor 16
, And a tray lower limit switch 17 is provided at the lower end of the tray guide 10. The drop sensor 16 is connected to the discharge tray 8
It is configured to detect that the uppermost sheet 18 stacked on the uppermost position is at the lower limit position in the allowable range of the drop between the sheet 18 and the above-described sheet discharge unit 6. The allowable range of the drop is set to a range in which the sheets 18 discharged from the sheet discharge unit 6 are surely accumulated on the sheet discharge tray 8. Tray lower limit switch
Reference numeral 17 detects that the discharge tray 8 has reached a lower limit position, which is a limit at which it can be lowered.

Further, as shown in FIG.
A ROM 20 that is a read-only memory that stores control procedures shown in FIG. 1 described later in advance, and a RAM 21 that is a rewritable memory that is used as a storage area and a work storage area for input data and serves as a main storage device And a central processing unit (hereinafter referred to as CPU) 22 for controlling the operation of the tray elevating motor 14, the display unit 24 and the driver 25 connected via a bus according to the control procedure stored in the ROM 20. . The ROM 20, RAM 21 and CPU 22 constitute control means.

The above-mentioned CPU 22 is connected to a timer 23 for measuring a fixed time. The time measured by the timer 23 is determined by taking into account the amount of paper discharged from the paper discharge unit 6 per unit time so that the uppermost paper 18 on the paper discharge tray 8 at the end of the clocking is the upper limit of the allowable difference range. Is set to a time that does not exceed Further, the CPU 22 has a drop sensor 16, a tray lower limit switch 17, a driver 25 for driving the tray elevating motor 14 based on a control signal of the CPU 22, and a sheet 18 on the sheet discharge tray 8 in a full state. And a display unit 24 for displaying information indicating the fact. The driver 25 is connected to the tray elevating motor 14. Further, when the print switch of the copying machine 2 is turned on, the CPU 22 receives a copy operation signal 26 indicating the start of the copy operation.

In the above configuration, the discharged paper stacking device 1 is controlled by the CPU 22 based on the flowcharts of FIGS. 1 (a) and 1 (b).
Will be described. FIG. 1 (b) shows a subroutine for tray position adjustment (S4, S13, S18) in FIG. 1 (a).

The following control is executed after the original is set in the copying machine 2 and the number of copies is set.

First, before the copy operation signal 26 indicating the start of the copy operation of the copying machine 2 is inputted (S1), the tray lower limit switch 17 is turned on.
It is determined whether or not the switch is ON (S2). If the tray lower limit switch 17 is OFF, the process returns to S1 and waits for the input of the copy operation signal. On the other hand, if the tray lower limit switch 17 is ON in S2, the display unit 24 displays a state in which the paper discharge tray 8 is full of paper 18 (S3).

After that, the operation shifts to tray position adjustment operation (S4). At this time, first, ON / OFF of the head sensor 16 is determined in S5,
If the drop sensor 16 is ON, the operation of S5 → S8 → RETURN → S2 → S3 → S4 → S5 is repeated unless the paper 18 on the discharge tray 8 is removed, and it is not possible to shift to the copy operation.

Here, when the paper 18 on the paper discharge tray 8 is removed, S5
Then, the drop sensor 16 is turned off, so that the tray lifting motor 14 is driven by the driver 25 to raise the sheet discharge tray 8 (S6). This raising operation is a returning operation of the paper output tray to the initial position, which is performed when the drop sensor is turned from ON to OFF while the tray raising / lowering motor is not operating. The operation is not performed until the discharge tray 8 reaches the head sensor 16 and the head sensor 16 is turned on. Thereafter, when the drop sensor 16 is turned on (S7), it is determined again whether or not the tray lower limit switch 17 is turned on (S7).
8). If the tray lower limit switch 17 is ON, S
3 and display the full state of the paper 18 on the display 24,
The operations of S2 to S4 are repeated until the sheet 18 on the sheet discharge tray 8 is removed. On the other hand, in S8, the tray lower limit switch 17
Is OFF, the tray raising / lowering motor 14 is rotated, and the discharge tray 8 is lowered until the head sensor 16 is turned OFF (S
9). Thereafter, when the drop sensor 16 is turned off (S10), the tray elevating motor 14 is stopped, and the discharge tray 8 is positioned (S11). Thereafter, the flow returns to S2, and the ON / OFF of the tray lower limit switch 17 is determined again. At this time, the discharge tray 8
Since the tray has risen, the tray lower limit switch 17 is OFF, and the process returns to S1 to complete the copy preparation.

Next, when the print switch of the copying machine 2 is turned on and the copy operation signal 26 is inputted (S1), the timer 23 is reset (S12), and the tray position is adjusted again by S5 to S11 (S13). , And ON / OFF of the tray lower limit switch 17
Is determined (S14). This operation is for responding to the case where the tray lower limit switch 17 is turned on while the paper 18 is being ejected.
If it is turned on (S14), the copying operation is stopped (S15), and the display unit 24 displays a full load state (S16). Then, the operations of S16 to S18 are repeated until the sheet 18 on the sheet discharge tray 8 is removed. Then, when the sheet 18 on the sheet discharge tray 8 is removed, the process returns to S1 and restarts, and the operation after S1 is performed again.

On the other hand, if the tray lower limit switch 17 is OFF in S14, the timer 23 is started (S19). Thereafter, when the set time of the timer 23 is reached, the process returns to S12 to reset the timer 23, and the tray position is adjusted in S13. Since then, S12 ~
The operation of S21 is continued until the copying is completed (S12) or the tray lower limit switch 17 is turned ON (S14). Here, when the copy is completed in S21, the timer 23 is stopped (S2
2) Return to S1 and prepare for restart.

〔The invention's effect〕

As described above, the discharge sheet stacking device of the present invention is configured such that the uppermost sheet stacked on the sheet discharge tray or the upper surface of the sheet discharge tray in a state where the sheets are not stacked are connected to the sheet discharge section by A head sensor for detecting that the head is at the lower limit position in the allowable range of the head, a timer for measuring a predetermined time, and a paper output tray on the paper output tray in which the uppermost sheet or paper is not stacked by the head sensor. When it is detected that the upper surface is at the lower limit position, a timer is started in accordance with the discharging operation of the sheet onto the discharge tray, and when the timer is finished, the tray elevating motor is turned off. Operating means for lowering the sheet discharge tray to operate the tray elevating motor when the drop sensor detects that the uppermost sheet on the sheet discharge tray has reached the lower limit position. It is a configuration that.

Therefore, since the control of raising and lowering the discharge tray is performed at regular time intervals by the timer, it is possible to reduce the load of each load such as the tray raising and lowering motor on the tray that constantly controls the raising and lowering of the tray. The life of these loads can be extended. Further, the control unit can perform other control while not performing the tray lifting / lowering control.
Further, when the range of the head is set by the upper limit level sensor and the lower limit level sensor, the number of sensors can be reduced, and the cost can be reduced.
In addition, when the paper is smoothly discharged from the paper discharge unit, the paper discharge tray does not move up and down, but only performs an operation of gradually descending as time passes when the paper is discharged. In other words, it is possible to continuously accumulate the sheets on the sheet, that is, for example, to continuously discharge the sheets from the sheet discharge unit of the copying machine.

[Brief description of the drawings]

1 to 3 show an embodiment of the present invention. FIG. 1A is a flowchart showing the operation of the discharged paper stacking device. FIG. 1B is a flowchart showing a subroutine for tray position adjustment shown in FIG. FIG. 2 is an explanatory view showing a structure of a main part of the discharged paper stacking device. FIG. 3 is a block diagram showing a control circuit of the discharged paper collecting apparatus. 1 is a paper output stacking device, 2 is a copying machine, 6 is a paper output unit, 8 is a paper output tray, 14 is a tray elevating motor, 16 is a drop sensor, 17
Is a tray lower limit switch.

Claims (1)

(57) [Claims] A discharge tray for receiving and stacking sheets discharged from the discharge unit below the discharge unit, wherein the discharge tray is moved up and down by a tray lifting motor; A head for detecting that the uppermost sheet stacked on the sheet discharge tray or the upper surface of the sheet discharge tray in a state where sheets are not stacked is located at a lower limit position in an allowable range of a difference between the sheet and the above-described sheet discharge portion. A sensor, a tray lower limit switch for detecting a lower limit position of the discharge tray, a timer for measuring a predetermined time, and a discharge tray in a state where the uppermost sheet or sheets on the discharge tray are not stacked by the drop sensor. When it is detected that the upper surface is at the lower limit position in the allowable range of the drop between these and the above-described paper discharge unit, a timer is started in accordance with the operation of discharging the paper onto the paper discharge tray. When the time counting by the timer is completed, the tray elevating motor is operated to lower the sheet discharge tray, and the top sheet on the sheet discharge tray is moved by the drop sensor in the allowable range of the drop from the discharge section. Control means for stopping the tray raising / lowering motor and clearing the timer when it is detected that the lower limit position has been reached, and the discharge tray lowered with the discharge of paper is moved to the lower limit position by the tray lower limit switch. An ejected paper stacking device characterized by lowering gradually until it is reached.